The present invention relates to an inkjet-recording medium, a method for forming inkjet print with the inkjet-recording medium, and inkjet print produced by the method for forming an inkjet print.
One of the processes for outputting image data and character code data, which are produced by, for example, personal computers, onto recording media such as paper and overhead transparency films includes inkjet recording in which an image is produced by discharging an ink containing a water-soluble dye to a surface of a recording medium through a recording nozzle of a printer, the recording nozzle being driven by, for example, an electric field, heat, or pressure.
Media including an ink-receiving layer formed on a surface of a base have been used for such inkjet recording. Paper has been used as such a base for a long time. In recent years, there have been demands for an inkjet-recording medium that can be printed on with near photographic-quality. Hence, for example, bases made of resin films such as polyester films having high surface smoothness and excellent water-resistance and bases made of resin-coated paper having polyolefin resins coated on both sides of the papers have become more widely used.
To quickly absorb inks and to prevent inks from overflowing and bleeding even when printed dots overlap each other, ink-receiving layers having porous structures produced by coating bases with binder resins, for example, polyvinyl alcohols containing fillers such as fine particle alumina hydrate or fine particle silica, have been used.
Dye-sublimation thermal transfer printing has generally been performed so as to form an image-protecting layer made of a transparent thermoplastic resin on a dye-receiving layer with an image, thus improving lightfastness and resistance to indoor fading and discoloration. For ink-jet recording, it has also been attempted to form such an image-protecting layer on an ink-receiving layer with an image (Japanese Unexamined Patent Application Publication No. 8-252985, in particular, Claim 1, paragraph [0001], and the like).
However, as is the case with such dye-sublimation thermal transfer printing, when an image-protecting layer is disposed on an ink-receiving layer with an image formed by inkjet recording, problems with, for example, a decrease in lightfastness and an increase in ink bleeding during storage have sometimes arisen. In particular, these problems have been pronounced when using a base that cannot absorb water (for example, a resin-coated (RC) paper base or a polyethylene terephthalate (PET) base). When a water-absorbing paper base is used, the degree of reduction in the lightfastness of an image and the occurrence of ink bleeding are low compared to the case with a base that cannot absorb water. However, there has been a problem that the effect of improving indoor fading and discoloration is unsatisfactory.